of san francisco



1.1. HALL; I I I ,APBARATUS'HR OPERATING ELEVATORS, Y; N-0. 605,044-; f I Patented May 31,1898. v I

(N6 Model) I Witness e; Inventor I Attorney application not Apa'l1Z9,-189'Z Serial UNITED-{ TATE COFRAN-JIY. HALLOF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO Tim CAH'ILLY aHA-LnELEvAToR' OOMPANY,- OF SAME LACE.-

- 'A|="|=Am\"r,us FOR/OPERATING ELEVATORS;

- sPEc ImoAT Ion'roimiiigpmofmettei rate n1; No.- 605,044', dated 'M'ay 31,1898.

To all whorntit"ma i i Q zen of the United States,-residing in th ecit y and county of San Francisco, State oflCali-y fornia, havei nvented certain .new andfiiseful' Improvements in Apparatus for Operating Elevators, (for which Letters Patent have been granted in Great Britain, No. 1,040,

dated January-17,1894, andin France, No.

the followingis a specification.

My invention relates to apparatus for operatingelevat'ors for raising and lowering 235,580, dated January '17,. ?18 94, of which people andmerchandise and to a method, of

. formed."

My inventidnconSists in resistingor coun o t'erbalancin g a predetermined portion of the weight tor load to, be; raised, preferablythe'- cag'ejand 'one half"of .as efrvice load, by means of jaihydraulic pi'sten sustaining a constant pressure derivedE,-f rom a receiver under presv "theji'.

suf'rleand in applyin the operating power, to.

1stonEthrough-the fluid acting thereon by the medium of; anauxiliary-cylinder and 'pi'ston-operated by mechanical connection withthe driving power; I

; the safety attained byhydraulie apparatus- .whichforms a positive resistance to falling or sudden movements of a cage or load also,

' The objects ofmy'invention are, to secure to equalize asnearly as possible the amount of power required in moving the cage'andits load upward and downward and by such di: vision reduce the maximum amount of power and consequent capacity of the motor or the iinpelling agent, whatever it may be.

To this end I construct apparatus as shown in the drawing herewith. f 1

The drawing is an elevation, partiallyinsection, skewin an application of my invention by means mite reciprocatingpistoninterposed betweenfthcmain hydraulic piston and a receiver or soumezof fluid-supply. q

Said drawing showsa receivercontaining the working fluid. L'I-his ispreferab1e,'

No. 634,423, uiofmoaet fra ma in England J se '17, 1894, Ne. 1,o4o,a na in Fralioafl'anuary 17, 1894,-N0-.235,580;' I i I I be .oil,- ;i'- gly cerin,' and water or other com-' Beit known that I, CQFRAN I,.HALL,-'a citi pounds of a lubricating and non-'congealing nature.- Th'e pressure in the receiver 1 can .be derived from compressed air, that partially fills the'space and exerts an elastic pressureonlthe liquids, any waste of air being lis'uppliedthroughthe nipples 2 from an air pump. or compressor. I also employ steam-as the compressing fluid, in which case the reiceiver -l issetvertically, so that the area of the liquidexpose'd'to heat will be as small as possible to prevent condensation of the steam and overheating of the water.

cylinder.

4 isthe t-ached; to-a movableframe 6, in which are mounted the movable ropepulleys 7, corresponding to the stationary rope-pulleys 8 at the other. end of, the cylinder 3. Around ,thesepulleys 7 and 8, which constitute the ;9r, -that extends-to a cage or load to be raised or lowered, commonly by passing over pulle ys at the topg 'butthis being well under- "stood and not .forming a part of my inven- ,tion' -doe snot require ill ustration.

Betweenthe receiver 1 and the cylinder 3 'isplaced theiauxiliary hydraulic device by which the operating power is applied. Said "device can be driven by a belt from an electric motor or other suitable power. A pipe 13 formsa; connection between the receiver 1 and the chamber 28 in the cylinder '3, with which the auxiliary hydraulic device is also connected. The receiver 1 being partially filled with liquid-f0r example, up to the line l 5 and above this line with air at the required sure equal to its area multiplied into the pressure inthe receiver 1,- and this area and pressure, as before explained, are. so arranged that the draft or tension on the vertical rope '20 will equal or counterbalance the load to be raised, or somerpredetermined part thereof, as the power required inraising or lowering loads will be as nearly the same as the variation of service loads will permit.

To produce movement each way, I, provide the auxiliary hydraulic device above referred Inthe drawing,3 is the main hydraulic piston, and 5' the piston -rod, at== pressure-the piston 4 is subjected to a pres usual multiplying devices, is. wound the rope to, which controls the flow of liquid between the receiver Land the chamber 14 conscquentl controls the movements of the piston 4 and hf the load moved upward or downward, thereby acting either as a retarding force in lowering a heavy load or as an impelling force in raising a load.

The receiver 1 is partially filled with liquid and with airor steam to produce pressure. The main hydraulic cylinder 3 is closed at both ends and provided with a trunk-piston rod 5, the object of which is to partially occupy the cylinder 3, and thus reduce its cubical capacity for liquid, so that the amount of liquid contained in the annular chamber 27, surrounding the said trunk-piston, shall be the same as that contained in an equal length of the chamber 25, with which said annular chamber communicates and into which it discharges by the coincident movements of pistons 26 and 4, whereby the two cavities are complementary to each other and the combined capacity of thetwo is a constant volume. The auxiliary piston 21 is moved by the piston-rod 22, attached to a cross-head 48, through which passes a screw 23, drivenby the pulleys'24, the latter being arranged to receive open and ,crossed belts,

so that the screw 23 can be driven either way by an electric motor or any other suitable source of driving power. The pipe 13 connects' from the receiver 1 to the chamber 28 in the main cylinder 3, also to the chamber 26 of the auxiliary'cylinder 17, the chambers in front of the pistons in the main cylinder 3 and auxiliary cylinder 17 and the chambers 25 and 27 being filled with a constant quantity of liquid, which can circulate or pass from one chamber to the other by means of the. pipe 19. In this manner it will be seen that the main piston 4 exerts an outward 0r lifting force and draft on the vertical rope 20 in proportion to the difference of its area 011 the two sides and that in moving of the piston 21 by means of the screw 23 the main piston 4. will follow the same distance. In the pipe 13 I place a cook 18, which if closed will stop all motion of the pistons 4 21 and the connected gearing and can be employed as a positive stop at the extremes of the stroke of the main piston 4.

A valuable feature of this device consists in providing a water-abutment in the chamber 27 on the back of the main piston 4 and in adapting the apparatus for control by the piston 21 and the revolving screw 23, to which the motive power is applied.

Having thus described the nature and the objects of my invention, what I claim is In apparatus to operate elevators, a hydraulic cylinder and a piston therein, said cylinder in communication with a receiver containing fluid under pressure communicatingwith one side of the hydraulic piston to counterbalance a predetermined load on an elevator to which the apparatus is attached, a second hydraulic cylinder and a piston in communication with the receiver and with the other side of the main hydraulic piston so that movements of the auxiliary piston produce or permitlike movements of the main piston, in combination with an electric m0- tor or other power connected to the second or auxiliary piston, substantially as specified.

In testimony whereof I aflix my signature in presence of two witnesses.

COFRAN I. HALL.

Witnesses:

J os. B. KEENAN, H. J. LANG. 

